Settlements filed by government regulators in the U.S. and the U.K. show this manipulation happened in two ways: first, Barclays' traders attempted to steer rates up or down in order to benefit trades they had made to profit off of those rates. Separately, the filings show that during the financial crisis, Barclays tried to counter reports that it had financial troubles by changing the interest rate it reported.

So far, the scandal has been limited to Barclay’s, a big London-based bank that just paid $453 million to U.S. and British bank regulators, whose top executives have been forced to resign, and whose traders’ emails give a chilling picture of how easily they got their colleagues to rig interest rates in order to make big bucks. (Robert Diamond, Jr., the former Barclay CEO who was forced to resign, said the emails made him "physically ill" – perhaps because they so patently reveal the corruption.)

But Wall Street has almost surely been involved in the same practice, including the usual suspects — JPMorgan Chase, Citigroup, and Bank of America – because every major bank participates in setting the Libor rate, and Barclay’s couldn’t have rigged it without their witting involvement.

In fact, Barclay's defense has been that every major bank was fixing Libor in the same way, and for the same reason. And Barclays is "cooperating" (i.e., giving damning evidence about other big banks) with the Justice Department and other regulators in order to avoid steeper penalties or criminal prosecutions, so the fireworks have just begun.

The power of the financial sector has to be restrained by effective independent regulation.